1、competition 指競爭、角逐等行為時，是個抽象名詞，不可數。competition 作“比賽；競賽”解時，是可數名詞，有數的變化。

2、The very notion of price competition is foreign to many schools。價格競爭這個概念對于許多學校都很陌生。

3、There's been some fierce competition for the title。奪冠之爭一直都相當激烈。

4、I have to change my approach, the competition is too good now。我得改變方法，現在的競爭對手太強。